全文获取类型
收费全文 | 104831篇 |
免费 | 10953篇 |
国内免费 | 7707篇 |
专业分类
电工技术 | 8279篇 |
综合类 | 10096篇 |
化学工业 | 13641篇 |
金属工艺 | 6781篇 |
机械仪表 | 6811篇 |
建筑科学 | 7223篇 |
矿业工程 | 4314篇 |
能源动力 | 2733篇 |
轻工业 | 11512篇 |
水利工程 | 2991篇 |
石油天然气 | 3375篇 |
武器工业 | 1512篇 |
无线电 | 10690篇 |
一般工业技术 | 9740篇 |
冶金工业 | 6997篇 |
原子能技术 | 1726篇 |
自动化技术 | 15070篇 |
出版年
2024年 | 485篇 |
2023年 | 1542篇 |
2022年 | 3759篇 |
2021年 | 4936篇 |
2020年 | 3442篇 |
2019年 | 2610篇 |
2018年 | 2661篇 |
2017年 | 2992篇 |
2016年 | 2683篇 |
2015年 | 4281篇 |
2014年 | 5257篇 |
2013年 | 6637篇 |
2012年 | 8063篇 |
2011年 | 8474篇 |
2010年 | 7876篇 |
2009年 | 7548篇 |
2008年 | 7684篇 |
2007年 | 7505篇 |
2006年 | 6396篇 |
2005年 | 5095篇 |
2004年 | 4019篇 |
2003年 | 3132篇 |
2002年 | 3269篇 |
2001年 | 2890篇 |
2000年 | 2093篇 |
1999年 | 1079篇 |
1998年 | 1476篇 |
1997年 | 960篇 |
1996年 | 724篇 |
1995年 | 502篇 |
1994年 | 363篇 |
1993年 | 403篇 |
1992年 | 246篇 |
1991年 | 195篇 |
1990年 | 181篇 |
1989年 | 158篇 |
1988年 | 158篇 |
1987年 | 128篇 |
1986年 | 132篇 |
1985年 | 162篇 |
1984年 | 98篇 |
1983年 | 100篇 |
1982年 | 89篇 |
1981年 | 118篇 |
1980年 | 122篇 |
1979年 | 75篇 |
1977年 | 100篇 |
1976年 | 192篇 |
1975年 | 51篇 |
1973年 | 52篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
11.
12.
13.
14.
15.
Davide De Biase Giuseppe Piegari Francesco Prisco Ilaria Cimmino Ilaria dAquino Valeria Baldassarre Francesco Oriente Serenella Papparella Orlando Paciello 《International journal of molecular sciences》2021,22(7)
Sarcopenia is defined as the age-related loss of skeletal muscle mass, quality, and strength. The pathophysiological mechanisms underlying sarcopenia are still not completely understood. The aim of this work was to evaluate, for the first time, the expression of NLRP3 inflammasome in bovine skeletal muscle in order to investigate the hypothesis that inflammasome activation may trigger and sustain a pro-inflammatory environment leading to sarcopenia. Samples of skeletal muscle were collected from 60 cattle belonging to three age-based groups. Morphologic, immunohistochemical and molecular analysis were performed to assess the presence of age-related pathologic changes and chronic inflammation, the expression of NLRP3 inflammasome and to determine the levels of interleukin-1β, interleukin-18 and tumor necrosis factor alpha in muscle tissue. Our results revealed the presence of morphologic sarcopenia hallmark, chronic lymphocytic inflammation and a type II fibers-selective NLRP3 expression associated to a significant decreased number of immunolabeled-fibers in aged animals. Moreover, we found a statistically significant age-related increase of pro-inflammatory cytokines such as interleukin-1β and interleukin-18 suggesting the activation of NLRP3 inflammasome. Taken together, our data suggest that NLRP3 inflammasome components may be normally expressed in skeletal muscle, but its priming and activation during aging may contribute to enhance a pro-inflammatory environment altering normal muscular anabolism and metabolism. 相似文献
16.
Romero-Garcés A. Salles De Freitas R. Marfil R. Vicente-Chicote C. Martínez J. Inglés-Romero J. F. Bandera A. 《Multimedia Tools and Applications》2022,81(3):3603-3628
Multimedia Tools and Applications - The design of robots capable of operating autonomously in changing and unstructured environments, requires using complex software architectures in which,... 相似文献
17.
18.
19.
Deborah Oliveira De Fusco Leonardo Lucas Madaleno Vanildo Luiz Del Bianchi Aline da Silva Bernardo Rafael Roberto Assis Gustavo Henrique de Almeida Teixeira 《International Journal of Food Science & Technology》2019,54(7):2416-2424
Alcohol-free beer with isotonic properties is getting more popular and its production can be carried out by different production strategies; however, interrupted fermentation is still a challenge. Therefore, the objective of this study was to develop a low-alcohol isotonic beer (<0.5% v/v) by interrupted fermentation. Moreover, the major objective is to compare the developed product to commercial beverages (sports drinks, ‘Pilsen' regular beer, alcohol-free beers and low-alcohol isotonic beer). The beverages were evaluated based on pH, alcohol content (% v/v), total titratable acidity (mEq L−1), osmolality (mOsmol kg−1), bitterness International Bitterness Units, colour European Brewery Convention, total phenolic compounds (mg L−1 gallic acid), reducing and total sugars (%) and Na and K contents (mg L−1). The developed low-alcohol isotonic beer presented characteristics similar to sports drinks, with the advantage of being richer in phenolic compounds and suitable osmolality. Despite salts were added in its formulation, the grades attributed to all beers employed in the sensory evaluation, as well as the purchase intention did not present significant differences. 相似文献
20.